Expansion means for cooling aircraft cabins



March 28, 1950 H. J. wboo 2,502,194

, EXPANSION MEA NS.FOR COOLING AIRCRAFT CABINS Filed April 22, 1946 2 Sheets-Sheet 1 ll 55 h as l n [I 39 6 l 58 27 INVENTOR.

HOMER J. WOOD March 28, 1950 H. J. wooo 2,502,194

mgrmsionuaans FOR COOLING AIRCRAFT cums Filed A ri122, 1946 i 2 Shoets-$heet 2 INVENTOR. J WOOD ATTORNEY HOMER Patented Mar. 28, 1950 EXPANSION MEANS FOR COOLING AIRCRAFT CABINS Homer J. Wood, Los Angeles, Calif., assignor to The Garrett Corporation, LoxAngelea, CaliL, a corporation of California Application April 22, 1946, Serial No. 663,931

13 Claims. I (01. 62136) My invention relates to air cooling systems wherein air to be cooled is compressed, cooled, and then expanded through an air motor, such as a turbine, for example, whereby some of the power utilized in compressing the air may be recovered, and an eflicient cooling of the air accomplished. In such systems the air may befurther conditioned by extraction or addition of moisture for the purpose of imparting thereto to a desired humidity.

It is an object of the invention to provide a simple and compact assembly of parts which may be used in refrigerating systems of this character, but which is especially adapted for use in aircraft due to its compactness and light weight.

A feature of the invention is that this assembly of parts may be readily installed and removed as a unit. For example, it may be installed in an aircraft during summer when cooling of the aircraft air is desired, and may be removed during the winter months, or may be replaced at such time by air heating equipment.

It is an object of the invention to provide for use in an air cooling system a device including an air compressor and an expansion air motor associated with a heat exchanger which connects the outlet of the compressor with the inlet of the air motor, whereby power recovered from the compressed air may be applied to the compressor and may be also utilized to operate air pumping means for moving coolant air through the heat exchanger.

It is a further object of the invention to provide an air cooling mechanism which may be made into a unit adapted to be relatively quickly and easily installed and removed, this device having an air expansion turbine and a compressor in spaced relation and in axial alignment on oppos te sides of a structure by which the casings of the turbine and the compressor are supported, this supporting structure incorporating an air duct with a fan therein adapted to be driven from the shaft which extends from the rotor of the turbine to the rotor of the compressor.

A further object of the invention is to provide a refrigerating unit of the character set forth in the preceding paragraph having as a built in part of the structure a heat exchanger through which coolant air is moved by the fan, and having a valved bypass duct connecting the inlet of the compressor with the outlet of the turbine, whereby the quantity of air passed through the compressor, the heat exchanger and the expansion turbine may be proportioned in accordance with the need for cooling the air,

Further objects and advantages of the invention may be brought out in the following part of the specification.

Referring to the drawings which are for illustrative purposes only,

Fig. 1 is a partly sectioned front view of a preferred embodiment of my invention.

Fig. 2 is a plan view corresponding to Fig. 1, partly sectioned as indicated by the line 2--2 of Fig. 3 is a cross section taken as indicated by the line 3-3 of Fig. 2.

The refrigerating equipment shown in the drawings includes a supercharger or compressor l0, and an inter-cooler or heat exchanger divided into upper and lower portions l8 and 2| by a wall II, and an expansion air motor i2 01' turbine form. The compressor is of rotary or centrifugal form and hasa rotor l3 operating within a casing ll. This rotor l3 takes air from the compressor inlet l5 and forces this air through the casing l4 and duct members l6, as indicated by the arrows ll of Fig. 2. From the outlet duct members N5 of the compressor III, the air passes into the upper portion I! of the heat exchanger II and travels horizontally through the upper portion of the exchanger II as indicated by arrows l9. At the leftward end of the heat exchanger II, the air passes downwardly through a vertical passage member 20 to the leftward end of the lower pass 2| of the heat exchanger II and travels through the lower portion 2|, as indicated by dotted arrows 22. From the rightward or outlet end of the portion 2| of the heat exchanger II the now cooled air passes into a duct 23 as indicated by arrows 24, this duct 23, as shown in Fig. 2. extending forward under the inlet l5 and being connected by an L-shaped duct portion 25 with a longitudinal duct portion 26 which, as indicated in Fig. 1, communicates through an upwardly faced outlet 21 with the inlet 28 of the turbine housing 29.

The inlet l5 includes an enlargement 30 which connects with the rightward vertical extension 3| of a bypass duct 32. This bypass duct 32 has a horizontal portion 33 extending under. the compressor l0 and the turb ne l2 to a riser duct member 34 which communicates through an enlargement 35 with the outlet 36 of the turbine l2.

Across the upper and lower portions l8 and 2| of the heat exchanger l tubes 31 are extended for conducting a coolant in heat exchange relation to the air which passes through the heat exchanger II. The coolant employed in this device comprises a flow of air such as ambient atmospheric air which is brought in through a duct to the heat exchanger.

In connection with the heat exchanger there is pumping means for causing movement of air either by compression or by suction through the coolant passagesformed by the tubes 31 of the heat exchanger II which are shown in full lines in Fig. 3 and indicated by dotted lines in Fig. 1, wherein the flow of air through the tubes is indicated by arrows IT. This means for producing movement of air through the coolant passages of the heat exchanger is embraced in a supporting structure ll which is disposed between and connects together the casings or housings l4 and 29 of the compressor II and the turbine l2.

The supporting structure 8| embraces a,tubular wall a disposed in transverse relation to the compressor II and the turbine I2. The far end of the tubular wail I! has a flared portion 40. for connection with the near end ll of the heat exchanger l I. Within the tubular wall 39 there is a filler body It supported-by dijfluser webs 4| in such position as to form within the wall 39 an annular throat ll. Movement of air through the throat is accomplished by a fan 42 having blades or vanes 40 mounted on a rounded hub 41, the periphery 48 of which hub merges with the filler body 43. The fan member, consisting of the parts ll and 41, is supported by a shaft 48 carried by bearings 50 supported internally of the hollow members 43 and 41. A drive connection for the fan 42 is taken oil. from a shaft I which extends across the supporting structure and also traverses the hollow body 43, so as to 'carry power recovered by the rotor 52 of the turbine i2 to the rotor ii of the compressor l0. This take-oil! consists, in the present instance. of a bevel gear 53 flxed on ashaft SI, adapted to drive a bevel gear 84 which is fixed on the shaft 49. h

For control of air through the bypass duct 32 a valve 58 is provided, which is mounted on a shaft 51 extended within the duct 32 as shownin Fig. 3. This shaft 51 has on its outer end a crank 58 adapted to be swung by a motivating means 59, such as an electric motor or a hydraulic cylinder and piston arrangement, between closed and open positions, in accordance with the need for cooling of the air which is passed through the refrigerating unit.

All of the cooperating parts of the refrigerating mechanism hereinbefore described are connected together so as to form a unit of compact form and relatively light weight which may be readily installed and removed. The unitary structure is provided with mounting brackets I and II arranged at opposite ends thereof.

In the operation of the refrigerating unit, .air under compression is delivered to the inlet 15 leading to the compressor III. This air passes through the compressor l and through the heat exchanger ll, provided the valve ll of the bypass 32 is closed. In a cooled condition, the compressed air is delivered to the turbine l 2 wherein it passes through the inter-vane passages of the turbine rotor 52. Atthis time the air is ex-. panded and a portion of the energy released in the reduction of the air pressure as it passes through the inter-vane spaces of the turbine drives the turbine rotor I2 so that there is a recovery of power, such recovered power being carried by the shaft II to the rotor II of the compressor In to drive this compressor. A portion of this recovered power is transmitted from the shaft ii through the gears II and H to the shaft 40 so that the fan 42 will be revolved and will produce movement of coolant air through the coolant passages formed by the tubes 3'! of the heat exchanger II. In the present form of the invention the fan 42 produces a flow of coolant air through the heat exchanger ll by suction effect. That is to say, the blades 48 of the fan 42 force air through the throat 4! in the direction of the arrows 2, Fig. 2, so asto produce a reduction in pressure at the near end it of the heat exchanger, constituting a suction effect at the near endof the heat exchanger.

I claim as my invention:

1..In a refrigerating unit of the character described, the combination of an air inlet member; an air compressor to receive air from said air inlet member; an expansion air motor having an air outlet; a heat exchanger having air ducting for said air and ducting for a coolant, said air ducting connecting the outlet of said compressor with the inlet of said expansion air motor; power transmission means connecting the moving parts of said compressor with the moving parts of said air motor; pumping means between said compressor and said air motor for moving air through said coolant ducting of said heat exchanger; a power connection for driving said pumping means from said power transmission means; and a valved bypass connecting said inlet of said compressor with said outlet of said air motor.

2. In a refrigerating unit of the character described, the combination of:' an air compressor and an air motor in spaced relation; a supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising an air duct; air pumping means in said air duct for moving air therethrough; a shaft traversing said supporting structure from said compressor to said motor for transmitting power from said motor to said compressor; a power take 01!. from said shaft for driving said pumping means; and a bypass connecting the inlet of said compressor to the outlet of said motor.

3. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; a supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising an air duct; air pumping means in said air duct for moving air therethrough; a shaft traversing said supporting structure from said compressor to said motor for transmitting power from said motor to said compressor; a power take ofl from said shaft for driving said pumping means; a heat exchanger having air passages connecting the outlet of said compressor with the inlet of said motor; coolant passage means, one end of which is connected to said air duct of said supporting structure; and a valved bypass connecting the inlet of said compressor to the outlet of said motor.

4. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; a supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising a transverse cylindrical air duct; a filler body in said air duct defining an annular throat therein; a fan having peripheral vanes acting to move air through said throat; a shaft traversing said supporting structure from said compressor to said motor for transmitting power'from said motor to said compres- -withthe sor; and a power take off from said shaft for driving said fan.

5. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; a, supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising a transverse cylindrical air duct; a filler body in said air duct defining an annular throat therein; a fan having peripheral vanes acting to move air through said throat; a shaft traversing said supporting structure from said compressor to said motor for transmitting power from said motor to said compressor; a power take off from said shaft for driving said fan; a heat exchanger having air passages connecting the outlet of said compressor with the inlet of said motor; and coolant passage means, one end of which is connected to said air duct of said supporting structure.

6. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; a supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising a transverse cylindrical air duct; a filler body in said air duct defining an annular throat therein; a fan having peripheral vanes acting to move air through said throat; a shaft traversing said supporting structure from said compressor to said motor for transmitting power from said motor to said compressor: a power take-off from said shaft for driving said fan; and a bypass connecting the inlet of said compressor to the outlet of said motor.

7. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; a supporting structure connecting the casing of said compressor and the casing of said motor together, said structure comprising a transverse cylindrical air duct; 9. filler body in said air duct defining an annular throat therein; a fan having peripheral vanes acting to move air through said throat;

a shaft traversing said supporting structure from said compressor to said motor for transmitting power from said motor to said compressor; a power take of! from said shaft for driving said fan; a heat exchanger having air passages connecting the outlet of said compressor with the inlet of said motor; coolant passage means, one end of which is connected to said air duct of said supporting structure; and a valved bypass connecting the inlet of said compressor to the outlet of said motor.

8. In a refrigerating unit of the character described, the combination of: an air compressor and-an air motor in spaced relation; a supporting structure connecting the casing-of said compressor and the casing of said motor together, said structure comprising a transverse air duct; aflllerbodyinsaidairductdeflninganannular throat therein; a fan having move air through said throat; a shaft traversing said supporting structure from said compressor to said motor for transmittin power from said motor to said compressor; and a power take off from said shaft for driving said fan.

9. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced relation; an air duct; airpropelling means in said air duct for moving air therethrough; a power transmission means connecting the moving parts of said compressor moving parts of said air motor:

take-off from said transmission means for driving the air propelling means; and an airflow con..- nection between the inlet of said compressor and the outlet of said motor.

10. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced apart relation; an air duct positioned in the space between said-motor and compressor; air propelling means in said air duct for moving air therethrough; power transmission means connecting the moving parts of said motor, compressor and air propelling means; and a supporting structure defining a plurality of ducts including an airflow connection between the compressor inlet and air motor outlet.

11. In a refrigerating unit of the character dcscribed, the combination of: an air compressor and an air motor in spaced apart relation; an air duct positioned in the space between said motor and compressor; air propelling mean in said air duct for moving air therethrough; power transmission means connecting the moving parts of said motor, compressor and air propelling means; and a supporting structure defining a plurality of ducts including airflow connections between the outlet of the compressor and the inlet of the air motor, and between the inlet of the compressor and the outlet of the motor.

12. In a refrigerating unit of the character described, the combination of: an air compressor and an air motor in spaced apart relation; an air duct positioned in the space between said motor and compressor; air propelling means in said air duct for moving air therethrough; power transmission means connecting the moving parts of said motor, compressor and air propelling means; a supporting structure defininga plurality of ducts including airflow connections between the outlet of the compressor and the inlet of the air motor, and between the inlet of the compressor and the outlet of the motor; and means for regulating the airflow through the latter connection.

-13. In a unit of the character described for use with a heat exchanger, the combination of: a hollow wall structure defining a transverse air passage arranged for connection to the coolant passages of said heat exchanger; an air compressor housing flxed to one side of said hollow wall structure;- an air motorhousing flxed to the opposite sideof said wall structure; shaft means I extending from said air motor housing through vanes acting to apower ll 3,304,151

said hollow'wall structure to said air compres-. sor housing; an impeller in said air compressor housing driven by said shaft means; a rotor in said air motor housing connected to the opposite end of said shaft means so as to drive the same; air propelling means in said transverse air passage of said hollow wall structure, said air propelling means having a propeller mounted for rotation on an axis substantially parallel to said transverse air passage; tween said shaft means and said air propelling means to drive the same.

7 HOMER J. WOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Benkly July 7, 1930 Crawford Dec. 8, 1948 Number and a drive connection be- 

